The Department of Radiology and Radiological Sciences at Vanderbilt University Medical Center has been investigating polychromatic phase-contrast radiography (PC-R) for several years. This technique has many potential uses in medical imaging as a new contrast mechanism for soft tissue imaging. Unlike laboratories utilizing a Synchroton light source (which will not be available for routine medical facilities), our technique utilizes the concept of spatial coherence, rather than temporal coherence, to obtain images strongly influenced by phase effects. The major limitation of the technique is the low tube output of the microfocal X-ray tube needed for PC-R. This project proposes to partner the investigators in Radiology who have been developing PC-R techniques with an X-ray source available at the Free Electron Laboratory (FEL) facility located on the Vanderbilt campus through a new collaboration between physicists at the FEL laboratory and the imaging researchers in the PC-R laboratory. The newly-developed X-ray source is completely independent of the Free Electron Laser itself and has been designed to function as a "table-top" source that could be generally available to medical facilities. The X-ray beam produced by this source is largely monochromatic and has an extremely high spatial coherence. In addition, it has been designed to provide a high X-ray flux. These 3arameters make it a nearly-ideal source for PC-R. The project will initially optimize the imaging parameters for monochromatic PC-R with the unique X-ray source, by investigating different geometries and energies. Once the technique has been optimized, monochromatic PC-R will be compared to absorption radiography (with both the monochromatic source and with a traditional mammography machine) on surgical breast specimens. Image quality of all images will be judged by an experienced mammographer.